Toner for developing electrostatic latent image and manufacturing method thereof

Abstract

According to one implementation, a toner includes a toner mother particle and a convex portion on a surface of the toner mother particle. The toner mother particle includes at least a resin (1). The convex portion is formed from a resin particle including at least a resin (2). An average value of a length of a long side of the convex portion is within a range of 0.1 to 0.5 μm. A ratio between a Young's modulus of a non-convex portion of the toner mother particle (ER (1)) and a Young's modulus of a convex portion of the toner mother particle (ER (2)) is a value (ER (1)/ER (2)) within the range of 1.2 to 2.0.

What is claimed is: 
     
       1. A toner for developing an electrostatic latent image comprising:
 a toner mother particle; and 
 a convex portion on a surface of the toner mother particle, 
 wherein, 
 (a) the toner mother particle includes at least a resin (1); 
 (b) the convex portion is formed from a resin particle including at least a resin (2); 
 (c) an average value of a length of a long side of the convex portion is within a range of 0.1 to 0.5 μm; and 
 (d) a ratio between a Young's modulus of a non-convex portion of the toner mother particle (ER (1)) and a Young's modulus of a convex portion of the toner mother particle (ER (2)) is a value (ER (1)/ER (2)) within the range of 1.2 to 2.0. 
 
     
     
       2. The toner for developing an electrostatic latent image of  claim 1 , wherein the resin (2) is a resin including at least polyester resin. 
     
     
       3. The toner for developing an electrostatic latent image of  claim 1 , wherein the resin (2) is a resin formed from bonding a vinyl type polymerization segment and a polyester type polymerization segment. 
     
     
       4. The toner for developing an electrostatic latent image of  claim 3 , wherein a content ratio of the vinyl type polymerization segment in the resin (2) with respect to a total mass of the resin formed from bonding the vinyl type polymerization segment and the polyester type polymerization segment is within a range of 1 to 30% by mass. 
     
     
       5. The toner for developing an electrostatic latent image of  claim 3 , wherein a content ratio of the vinyl type polymerization segment in the resin (2) with respect to a total mass of the resin formed from bonding the vinyl type polymerization segment and the polyester type polymerization segment is within a range of 5 to 10% by mass. 
     
     
       6. The toner for developing an electrostatic latent image of  claim 1 , wherein a covering percentage of the convex portion with respect to a certain surface area of the toner mother particle is within a range of 5 to 25%. 
     
     
       7. The toner for developing an electrostatic latent image of  claim 1 , wherein a covering percentage of the convex portion with respect to a certain surface area of the toner mother particle is within a range of 10 to 20%. 
     
     
       8. The toner for developing an electrostatic latent image of  claim 1 , wherein the resin (1) is a resin including at least styrene-acrylic type resin. 
     
     
       9. The toner for developing an electrostatic latent image of  claim 1 , wherein an average particle diameter of the resin particle including at least the resin (2) is within a range of 50 to 500 nm. 
     
     
       10. A manufacturing method of the toner for developing an electrostatic latent image of  claim 1 , the method including at least the following:
 (1): preparing a dispersion liquid of a resin (1) particle formed from the resin (1); 
 (2): preparing a dispersion liquid of a resin (2) particle formed from the resin (2); 
 (3): forming a toner mother particle precursor by aggregating the resin (1) particle included in the dispersion liquid of the resin (1) particle; and 
 (4): forming a toner mother particle by fusing the resin (2) particle with the toner mother particle precursor in an aqueous medium. 
 
     
     
       11. The manufacturing method of the toner for developing an electrostatic latent image of  claim 10 , wherein (4) includes adjusting pH of the aqueous medium with a pH adjuster after attaching the resin (2) to the toner mother particle precursor. 
     
     
       12. The manufacturing method of the toner for developing an electrostatic latent image of  claim 11 , wherein the pH of the aqueous medium is within a range of 4 to 7 when measured at a liquid temperature of 80° C. in (4).